Conductor terminal for bushings



A. O. AUSTIN CONDUCTOR TERMINAL FOR BUSHINGS Filed July 29. 1922 2 Sheets-Sheet l INV EN TOR A TTOIINEY Oct. 8, 1929;

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CONDUCTOR TERMINAL FOR BUSHINGS Filed July 29, 1922 2 Sheets-Sheet 2 Fiy7 INVENTOR z z x I ATTORNEY Patented Oct. 8, 1929 UNITED STATES PATENT OFFICE ARTHUR O. AUSTIN, OF BARBERTON, OHIO, ASSIGNOR, BY IYIESNE ASSIGNMENTS, TO THE OHIO BRASS COMPANY, OF MANSFIELD, GIIIQ, A CORPORATION OF NEW JERSEY CONDUCTOR- TERMINAL FOR BUSHINGS Application filed July 29,

This invention relates to terminal members or fittings for insulator bushings used in connection with transformer housings, switches, roofs, walls potheads or other installations where it is desired to insulate a conductor from a member thru which it passes. The invention has for its object the provision of a terminal member by means of which low resistant electrical connection with the conductor is provided, which is easy to install or replace without disturbing the connections below the bushing which provides a tight closure for the opening thru the bushing, and which shall be of general improved construction and operation.

The invention is exem Jliiied in the combil nation and arrangement of the parts shown in the accompanying drawing and described in the following specification, and it is more particularly pointed out in the appended claims.

In the drawings:

Fig. 1 is a part section and part elevation showing one embodiment of the present invention.

Fig. 2 is a fragmentary view with parts in section showing a modification of the construction of Fig. 1.

Figs. 8. l, and 5 are plan views and Figs. (3, 7. and S are elevations respectively of diit'erent forms of conical bushings for securing the conductor within .its terminal fitting.

In the embodiment illustrated, the numeral designates a dielectric bushing having a cap 11 fitted to the end thereof and secured to the bushing in any suita le way as by cement 12. A cushion of yielding material 13 may be inserted betweenthe cap and the end of the bushing where desired. A circular flange 14 projects upwardly from the cap 11 forming a threat 15 through which the conductor 16 projects. An attaching lug 17 is soldered brazed or otherwise secured to the upper end of the conductor 16 and is tapered in opposite directions to form a denble cone having oppositely directed conical surfaces 18 and 19. An inner face of the flange 14 is tapered at an angle corresponding to the angle of the surface 19 as shown at 20, but the opening thru the flange is 1922. Serial No. 578,463.

larger than the corresponding portion of the lug 17 to permit a conical bushing 21 to be interposed between the two surfaces. The bushing 21 may be provided with a flange 22 to rest upon the upper edge of the flange 14:-

The conical bushing is preferably made in two sections to permit assembly. One suitable form of bushing is shown in Figs. 3 and 3 in which the bushing is divided into sep arate sections and 24k; dowel pins 25 being provided for holding the sections in registration. The sections may be provided with overlapping slots 26 and 27 to provide resiliency to the parts. This will permit the bushing to be pressed closely against the contacting surfaces so as to prov de ellicient elect ical connection between the parts.

In Figs. -1- and 7, the two halves and 29 are slotted as shown at .30 and 31 and the dowel pins 25 are omitted in this form. Reg istrationof the two parts will depend upon the supporting flange 22.

In the form shown in Figs. 5 and S, the lower portions of the sections and are slotted as shown at 3% and sections and 33 are each provided with a projecting lug 35 which fits into a corresponding recess in the complementary section.

The conical bushing 21 is preferably of uni form thickness so that it will support the lug 17 at the proper height and make good contact irrespective of its position in the flange If the bushing should not be moved as far down within the flange as it will go. this fact will not affect the height at which the lug 17 will be held as would be the case if the wall of the bushing were tapered or the walls not slotted since the slotting permits the bushing to accommodate itself to the interior of the flange 14 and provide a lining of uniform thickness even though the vertical postion of the bushing may be varied within limits. A weather cap 36 is provided with a tapered opening 37 for receiving the surface 18 of the lug 1?; the weather cap be ing secured to the fitting 11 by cap screw 38 threaded into the upper face of the cap 11. A yielding gasket 89 is interposed between the two caps to provide a tight joint. A sheet metal cover 40 may be bent around the edge of the gasket 39 and partially covering the opposite surfaces of the gasket to assist in providing electrical connection between the two caps. The weather cap 36 may be provided with an upper terminal socket 11 on which a conductor lead -12 is secured. The cap 11 may also have a contact lug 13 to which a conductor 14tmay be secured. The upper end of the tapered h1g1? may be perforated as shown at 15 to pro 'ide an eye for attaching the cord or other device for drawing the conductor 16 thru the bushing.

In the modified construction shown in Fig. 2, the upper terminal sleeve is omitted and connection is made with the cap 11 alone. The weather cap at is closed above the tapered lug 47 in which the upper surface i8 is tapered more abruptly than the lower surface 19. In place of the eye l5 the upper end of the lug may be threaded as shown at 50 to receive the end of an attaching eye or rod for drawing the conductor through the bushing.

In place of the form of gasket shown in Fig.1, a sheet metal gasket 52 is shown having circumferential extending corrugations to provide a yielding gasket which will afford good electrical connection between the contacting parts.

In connecting the terminal, the contact lug 17 is drawn up thru the throat- 15, the bush- 'ng 21 is slipped into place where it will iold the contact lug from dropping back. The gasket 39 is then put in place and is of such thickness that it will be tight, and at the same time permit the weathercap 36 to be drawn down tight so as to make good contact along the surface 18. The conical surface 18 and the lower conical surface 19 will have substantially the same pressure so that both surfaces form good electricalcontacts. The large areas these surfaces and the wedging action to which they are subjected afford a very low contact resistance. The upper terminal socket al'may be omitted or it may be used exclusively. It will be noted that a double contact path is provided betweenv the conductor 16 and the cap 11; one path being thru the contact surfaces 19 and 20 and the other path thru the contact surface 18 and the bolts 38 supplemented by the conductor covering A10 for the gasket 39;

The form of gasket shown in Fig. 2 may be substituted for that shown in Fig. 1, or a soft .metal gasket may be used. ll here the upper tapered surface of the contact lug is mace more abrupt than the lower surface as shown in Fig. 2, the connection between the weather cap and the contact lug will loosen more readily than that between the contact lughand the cap 11 which may be desirable in removing the connection so as not to pull upwardly on theconductor 16 which might loosen the connection of the con ductor below the bushing. it will be seen that the construction affords electrical connection between the conductor and the eX- ternal lead in which here are large contact areas held together by high pressure, so to reduce the resistance of the contacts to a minimum. The wedging action assists inaterially in securing the desired pressure be tween the contact surfaces. The double contact path between the conductor and the cap also assists in reducing the resistance in the circuit. No rotation is required in installing the parts so that a direct clamping action is brought to bear on the gasket, and there is no danger of twisting the conductor 16.

All 00 nections including those with the external leads may he soldered or brazed with tne exception of the protected contacts within the weather cap and the gasket surface. None of the supporting parts for the conductor 16 r small enough to drop thru the throat 5 so that there is no danger of losing small p rts thru the bushing. An attachment is pron which it ma be crawn through the bushand held in place until it is locked against .rn movement by the conical bushing 21. The maximum diameter of the lug 1'? must, of corn e, be small enough to pass thru the throat 15. The parts are so made that they will not go together unless they are in proper position, and the lug 17 cannot be tightened in place except at the proper height due to the uniform thickness of the conical bushing 21, the bushing being slotted so to ap proximately conform to the tapered terminal.

he shoulder 22 provides a place so that a screw driver or blade may be inserted between it and the lip 14 to loosen the bushing terminal.

1 claim:

1. In combination, a conductor, a support having a tapered opening into which said conductor extends with the body of said conductor projecting from the smaller end of said opening, said conductor having contact portion fixedly secured thereto and tapered to correspond with said opening, said tapered contact portion being disposed within the tapered portion of said opening, and a split conical sleeve formed in two separable sections interposed between said contact portion and the wall of said opening, the smaller end of said opening being large enough to permit the passage of the-tapered contact portion of said conductor therethrough.

2. In combination, a conductor having a tapered contact portion at one end thereof with the conductor extending from the smaller end of said contact portion, a support provided with a tapered opening surrounding said tapered contact portion, and a split.

sleeve formed in two separable sections and end of the conductor by having walls of substantially uniform thickness throughout interposed between said contact portion and support.

3. Means for supporting a conductor in adielectric bushing comprising a fitting se cured to said bushing and having a tapered seat with the smaller end of said seat directed towards said bushing, a conductor extending through said bushing and having a tapered contact portion disposed within said tapered seat, and a longitudinally split separable conical sleeve interposed between said conductor and seat.

at. Means for supporting a conductor in a dielectric bushing comprising a cap secured to said bushing and provided with a tapered opening, the smaller end of said opening being directed towards said bushing and forming a contact seat, a conductor in said bushing having a tapered contact member of a size to pass through said opening, and a longitudinally split separable conical sleeve removably interposed between said conductor and seat for en aging the tapered portion of said conductor to support said conductor in said seat.

5. In a dielectric bushing, a conductor extending through said bushing and having a tapered contact lug secured to the outer end thereof, a cap for said bushing having a tapered opening therethrough in position tosurround the tapered lug on said conductor, the inwardly directed end of said opening being the smaller and being of a size to permit the passage of said lug therethrough, and a separable split collar arranged to be removably seated in said opening for retaining said lug in position therein, said collar having means thereon for limiting its movement into said opening to fix the height of said conductor when held thereby.

6. In a dielectric bushing, a conductor extending through said bushing, a fitting secured to said bushing and having a tapered opening forming a seat, the smaller end of said opening being directed inwardly, a tap ered bearing member on said conductor, a conical sleeve interposed between said bearing member and the wall of said opening, and means other than said conductor tor pressing said bearing member into said tapered opento support said conductor and provide electrical contact between said conductor and fitting.

7 In a dielectric bushing having a conductor extending therethrough, a cap secured to said bushing and having a tapered opening therein forming a seat for supporting said conductor, a tapered lug on said conductor disposed within said tapered opening, a cover cap for said opening, means for clamping said cover cap to said bushing cap and for pressing said lug into said opening, and yielding packing interposed between said caps to form a liquid-tight oint therebetween While permitting pressure to be exerted by said cover cap on said lug.

8. In combination, a conductor having a contact portion fixedly secured thereto and provided with oppositely tapered contact surfaces, a separable housing having seats for receiving said tapered surfaces, one of said seats opening to the exterior of the housing, the opening being of sufficient size to permit passage of said contact portion therethrough, a split tapered sleeve interposed between the last said seat and said contact portion, and means for clamping said housing together to hold said contact portion in said seats.

9. In combination, a conductor having a contact member fixedly secured thereto and provided with oppositely tapered portions, a separable housing having oppositely tapered seats for receiving said tapered portions, one of said seats opening to the exterior of the housing, the opening being of suilicient size to permit the passage of said contact member therethrough, a split tapered collar inter posed between the last said seat and said con tact member, and means engaging the parts of said housing for moving said seats toward each other to clamp said seats on said contact member.

10. In combination, a conductor having a contact member fixedly secured thereto and PlOdtlGtl with oppositely tapered surfaces, a terminal member having an opening therethrough providing a seat for one of said tapered suri'aces, said opening being sutiiciently large to permit said contact member to pass therethrough, a split conical sleeve movably interposed between said contact member and seat, and a clamp having a tapered seat for engaging the oppositely tapered portion of said contact member for forcing said contact member into the seat formed by the opening in said terminal member.

11. A dielectric bushing having a conductor extending therethrough, a cap secured to said bushing and having a tapered opening therein, a contact lug secured to said conductor and having oppositely tapered surfaces, the inner one of which is arranged to register with the opening in said cap, and a cover cap for closing said opening having a tapered seat therein for receiving the other tapered surface of said contact lug and for clamping said lug in said opening to hold said conductor in place and to form low resistance electrical connection therewith.

12. A dielectric bushing having a conductor provided with a contact lug projecting therefrom, said contact lug having oppositely tapered outer and inner portions, a fitting secured to said bushing and having a tapered opening therethrough forming a seat for the inner end of said contact lug, a split cone bushing interposed between said seat and lug, a weather cap having a conical seat on the outer end of said lug and means for clamping said Weather cap to said fitting to form a cover for the opening therein, and to force the tapered sections on said lug into their respective seats.

13. A dielectric bushing having a fitting secured thereto, a conductor extending through said bushing and having a tapered contact portion seated in said fitting, a cover cap for said conductor arranged to press said contact member in its seat, threaded means for connecting said cover cap to said fitting and a conducting gasket interposed between said cap and fitting to form electrical connection therebetween.

1%. In combination a conductor, a support 7 for said conductor having a tapered seat, a contact member on said conductor having oppositely tapered surfaces difiering from one another in angularity, the outer one of said surfaces having the greater degree of angularity and a clamping member engaging said outer tapered surface of said contact member for holding said contact member in position.

15. In combination a conductor having a Contact member thereon provided with oppositely tapered surfaces of different angularity, a seat for one of said surfaces and a ciamping member for engaging the other of said surfaces to hold said contact member in said seat, the tapered surface in engagement with said clamp being more abruptly tapered than the surface contact in said seat so that said clamp will be released from its surface more readily than said seat.

16. A dielectric bushing, a fitting secured to said bushing having an opening providing a tapered seat, a conductor having a contact member thereon provided with an inner tapered surface disposed Within said seat, a cover. cap for said conductor having a tapered opening for receiving the outer end of said contact member, said outer end being tapered more abruptly than the inner end of said contact member to facilitate removal of said cover cap Without exerting outward force on said conductor.

In testimony whereof I have signed my name to this specification on this 25th day of July, 1922.

ARTHUR O. AUSTIN. 

